Correct copied variable name

group_vars/matrix_servers

@@ -1349,7 +1349,7 @@ matrix_synapse_app_service_config_files: |
 # cactus-comments web-server port.
 #matrix_cactus_comments_container_http_host_bind_port: "{{ '' if matrix_nginx_proxy_enabled else '127.0.0.1:' + matrix_cactus_comments_container_port | string }}"
 
-matrix_corporal_systemd_required_services_list: |
+matrix_cactus_comments_systemd_required_services_list: |
   {{
     (['docker.service'])
     +